Prime Minister Jacinda Ardern has moderate Covid-19 symptoms and is "doing okay" at home as a big week in Parliament gets under way.

Ardern was sent to home isolation when her partner Clarke Gayford contracted the virus last week, and on Saturday she herself tested positive.

Their daughter Neve also tested positive on Wednesday.

Housing Minister Megan Woods, who filled in for Ardern's media slots this morning, told AM that Ardern was "doing okay".

"As she described on Saturday, she's got moderate symptoms but like anyone else with Covid she needs to take this a day at a time and she needs to rest up."

Unfortunately, Ardern was not well enough to chair Cabinet remotely on Monday or to deliver her speech virtually during the lockup for Monday's pre-Budget release of the landmark Emissions Reductions Plan.

Woods said Ardern was gutted to not be in Parliament.

"Obviously she's gutted not to be here. It's a really big week here in parliament [with] obviously the Budget and the Emissions Reduction Plan and we are gutted not to have her here."

A spokesman said Ardern's participation in events this week - including the Budget - would depend on whether she was well enough each day.

Last week while Ardern was isolating but before she tested positive for Covid-19 she chaired Cabinet remotely and took part in Parliament's proceedings.

Ardern had been symptomatic since Friday.

"Despite best efforts, unfortunately, I've joined the rest of my family and have tested positive for Covid-19," she said.

"To anyone else out there, isolating or dealing with Covid, I hope you take good care of yourselves!"

The Prime Minister will be required to isolate until the morning of Saturday, May 21.

Travel arrangements for her trade mission to the United States are unaffected at this stage.